矿石经过粗碎后的直径一般为（）左右。
A.100mm.
B.200mm
C.300mm
D.400mm
参考答案：A
下面各数中不读出“零”的数是（ ）
A．905.7
B．300.05
C．120.44
D．1109003
—You look unhappy . What’s wrong ?
—I find ____ difficult ______on well with my classmates
A．it; to get
B．it ; getting
C．that ; to get
D．that ; getting
